The function of the heart may be seriously impaired if any of the heart valves are not functioning properly. The heart valves may lose their ability to close properly due to, e.g., dilation of an annulus around the valve, ventricular dilation, or a leaflet being flaccid causing a prolapsing leaflet. The leaflets may also have shrunken due to disease, e.g., rheumatic disease, thereby leaving a gap in the valve between the leaflets. The inability of the heart valve to close properly can cause a leak backwards (i.e., from the outflow to the inflow side), commonly referred to as regurgitation, through the valve. Heart valve regurgitation may seriously impair the function of the heart since more blood will have to be pumped through the regurgitating valve to maintain adequate circulation. Heart valve regurgitation decreases the efficiency of the heart, reduces blood circulation, and adds stress to the heart. In early stages, heart valve regurgitation leaves a person fatigued or short of breath. If left unchecked, the problem can lead to congestive heart failure, arrhythmia, or death.
Functional tricuspid regurgitation (TR), which accounts for the majority of all TR cases, occurs as a result of dilatation of the tricuspid annulus and enlargement of the right ventricle. These mechanisms are most often secondary to pulmonary hypertension, RV dysfunction, and left-sided valvular heart disease. Although early investigators hypothesized that TR would resolve upon correction of left-sided heart disease, subsequent studies have shown that severe TR often persists after left-sided valve interventions. Additionally, functional TR is increasingly recognized as a source of morbidity and a predictor for poor long-term survival.
Heart valve disease, such as valve regurgitation, is typically treated by replacing or repairing the diseased valve during open-heart surgery. Given that in functional TR the native valve leaflets exhibit no abnormal morphology, annular remodeling with a prosthetic ring has become the current gold standard for treatment; however, open-heart surgery is highly invasive and is therefore not an option for many patients. For functional TR patients too sick to undergo open-heart surgery due to other comorbidities or previous heart surgeries, a percutaneous treatment option is desirable. One such method is to position a structure between the valve leaflets so that the leaflets “coapt” against them, thereby helping to block regurgitant flow. However, to date designs for such “coaptation elements” fall short for one reason or another, including susceptibility to deformation over time that leads to a recurrence of regurgitation.